[Study on apoptosis of human stomach SGC-7901 cells induced by extracts of Solanum lyratum].

Objective: To investigate the effects of extracts of Solanum lyratum (ESL) on the apoptosis of Human stomach cancer SGC-7901 cells.

Methods: Dried whole herbs of Solanum lyratum were extracted by boiling distilled water. SGC-7901 cells were randomly divided into control group, ESL-treated groups (12.5 g/L, 25 g/L, 50 g/L) and the positive control (25 mg/L DDP) group. The growth inhibitory rate was evaluated by MTT assay. Morphological changes of apoptosis were observed with fluorescence microscope. Cell apoptosis rate was determined by flow cytometry. Expressions of bcl-xl, Caspase-9 and bid mRNA were detected by semi-quantitive RT-PCR. The activity of Caspase-3 was detected by Fluorospectrophotometry.

Results: Compared with control group, the cell proliferation inhibitory rate and apoptosis rate of human stomach cancer SGC-7901 cells increased obviously (P < 0.05). There were obvious changes of morphology of the SGC-7901 cells as the nuclear shrinkage, chromatin condensation and margination; The expression of bcl-xl mRNA decreased obviously (P < 0.05), the expression of Caspase-9 and bid mRNA increased obviously respectively (P < 0.05), and displayed effect in a dose-dependent manner in the SGC-7901 cells of the ESL-treated groups. The activity of Caspase-3 in the SGC-7901 cells of the ESL-treated groups were higher than that of the control group significantly (P < 0.01).

Conclusion: ESL can induce apoptosis and inhibit proliferation of the human stomach cancer SGC-7901 cells by regulating expression of bcl-xl, Caspase-9 and bid genes and strengthening the activity of Caspase-3.